Typescript ISO Date Type

README.md

ISODateTypes

Unfortunately this fails due to the type being too difficult for typescript to represent (which makes sense), but this was still a fun type.

ISODateTypes.ts

type OneThroughSix = 1 | 2 | 3 | 4 | 5 | 6;
type OneThroughNine = OneThroughSix | 7 | 8 | 9;
type ZeroThroughNine = 0 | OneThroughNine;
type ISOYear = `19${ZeroThroughNine}${ZeroThroughNine}` | `20${ZeroThroughNine}${ZeroThroughNine}`;
type ISOMonth = `0${OneThroughNine}` | `10` | `11` | `12`;
type ISODay = `0${ZeroThroughNine}` | `1${ZeroThroughNine}` | `2${ZeroThroughNine}` | `30` | `31`;
type ISOHours = `0${OneThroughNine}` | `1${OneThroughNine}` | `20` | `21` | `22` | `23` | `24`;
type ISOSecondsAndMinutes =
  | `0${ZeroThroughNine}`
  | `1${ZeroThroughNine}`
  | `2${ZeroThroughNine}`
  | `3${ZeroThroughNine}`
  | `4${ZeroThroughNine}`
  | `5${ZeroThroughNine}`;
type ISOMilliseconds = `${ZeroThroughNine}${ZeroThroughNine}${ZeroThroughNine}`;

export type ISOTimeString =
  `${ISOHours}:${ISOSecondsAndMinutes}:${ISOSecondsAndMinutes}.${ISOMilliseconds}`;
export type ISODateString = `${ISOYear}-${ISOMonth}-${ISODay}`;

export type ISODateTimeString = `${ISODateString}T${ISOTimeString}Z`;